Field
This technology relates generally to photonic devices, and, more particularly, to bi-stable photonic devices.
Background
Hysteresis has been observed in nature including ferromagnetic materials, crayfish receptors, and vertebrates. Also, hysteresis has applications in electronics such as Schmitt trigger device applications for reducing noise in signals. Proteresis has few appearances in literatures. Some examples are Prussian blue analogs, a magnetic polaron model, and magnetism of TiO2 clusters. A CMOS transition accelerator with proteresis has also been designed.
The hysteretic bi-stable device can be useful for regeneration of clean binary signals from noisy signals; however, the hysteretic bi-stable device delays the threshold function operation proportional to the hysteresis loop width and the conversion response time from the rate equations in semiconductor optical amplifiers (SOAs). A bi-stable device is a device that is like a switch in that it can only be in two possible stable states (bistability), for example “on” or “off”. In some systems, such as with binary delta-sigma modulators, a bi-threshold device is needed to prevent unwanted noise. The delay due to the hysteresis loop and SOA carrier life-time reduces their modulation rates; hence a new bi-threshold (bi-stable) device is needed with no delay or better yet negative delay which compensates the overall conversion time of the bi-stable device.